Can't pass emissions!

[greenbeer]

So I have ran the Bronco through emissions twice in the past couple of weeks failing each time. At first I thought it was the timing (was off 4 degrees). Nope, not that. Check for codes, no codes. All the emissions equip. is there and functional. The previous owner says the Cats are not that old. It only fails one of the four tests. HC (PPM). Idle limit: 220 Bronco: 643. What would cause this if no codes are being thrown. The motor has 59k miles on it. It's never had an emissions test before this, so the previous owner has no idea and neither do I.

Here is the test if you can read it...

 

[Donner]

There's actually links to your report if this copy is not clear for members.

 

[mawrazen]

Try adding an HHO generator.

It causes the engine to run cleaner. Also when you burn hydrogen the only byproduct of combustion is water.

Oxyhydrogen is a mixture of diatomic hydrogen and oxygen gases, normally assumed to be in a 2:1 atomic ratio, the same proportion as water. When ignited, this mixture combusts to water, making 142.35 kJ (34,116 gram calories) of heat for each gram of hydrogen burned: that is 286.97 kJ/mol of enthalpy.

 

[Donner]

I just read that's time for a tune up... have you done that already?

 

[btexpress]

Check for vacuum leaks, especially around the plenum gasket and the throttle body.

 

[toypaseo]

I wonder if you hit the interstate, ran it at high speed, then went directly to the emission station...?

My brother used to have a 1981 Audi 5000. Failed emissions. The emission guy told him to do the above. He passed with no problem.

 

[greenbeer]

Okay, it had a full tune up before I tried testing. I can't find a single hose out of place under the hood either. Wouldn't it run a little rough if it had a vacuum leak? As far as the driving at high speeds, I took the freeway to the emissions place... I just wonder if the cat is bad. How would I tell?

 

[Albino 94LTD]

Run some Acetone at 2oz:10Gal ratio for a couple tanks This was in the original Acetone thread. It might just help a little, I know it won't hurt, I've been running Acetone in the X since 2005 and you personally know it's still running

I had a chance to discuss the use of acetone in gasoline with a technician in a nearby automotive service center during a slow period. When I told him that I had been using acetone for the past week and noted little change in my mileage, he said that he was curious about something else that may be happening.

After the facility closed, he hooked my X up to the NY state-certified emissions tester. I got a printout and then compared it to the results I received when my vehicle was inspected last August. Since the August2004 inspection, I have cleaned the system using Seafom once, and cleaned the IAC once.

Date of test: 12Aug2004
HC = 0.39
CO = 7.66
NOx = 0.97

Date of test: 23Apr2005 with 1oz of Acetone per 10 gals 87 octane
HC = 0.24
CO = 5.63
NOx = 0.64

New York State test limits:
HC = 1.60
CO = 40.00
NOx = 2.50

 

[greenbeer]

Thanks Phil. Do you think Seafoam might help at all? The motor does only have 59k miles on it.

 

[Albino 94LTD]

Seafoam will reduce or eliminate any carbon buildup but I not sure it's the answer to your current issues. Won't hurt though.

B12 Chemtool is very similar to Seafoam. Most of those are detergents intended to clean up the fuel delivery system. Acetone is supposed to do that too over a long time period but the initial claim is better atomization of the fuel spray into the cyl. (if I remember correctly) resulting in more complete combustion.

I forget, was the Bronco driven frequently prior to your purchase? How is your fuel economy? 15-18hwy?

 

[greenbeer]

Before I bought it, it sat since April until I picked. The only real use it has had was the run from North Bend to Bothell, then the run we went on. Fuel mileage is awful. Haven't driven it enough to calculate but, it makes my 5.0 Explorer look like a Honda. It ate about a half of a tank on our trip. It has a 32 gallon tank...

 

[btexpress]

Fuel mileage and Bronco equal zippo, the two do not go together.

I wonder if the fuel is bad after sitting. I have had problems this year with both a pressure washer and snow blower that have sat for one year with fuel in the tanks, stuff smelled more like kerosene than gas. After draining and refilling with fresh fuel both started easily.

I remember my Dad having gas around forever, or so it seemed, but these new gasoliines seem to deteriorate at a much faster rate.
Just a thought anyway, you may have already run new fuel thru it.

 

[Albino 94LTD]

Hmm, yeah, gotta get some good juice through the fuel system and figure out how to reset the computer. That might be as easy as disconnecting the battery for a while, like our X's.

Definately run some detergent and good gas through it. I'd at least expect 12mpg if not more, but then you are running bigger tires and a lift with stock gears.

 

[frstxplorer]

I run an emissions test station in Ct. It looks like they have u doing a TSI (two speed idle test) and they have your gvw listed as 8500 there is no way a bronco should get a TSI test. It should be a Dyno test and tested at 2500rpm & 25 mph. I would Question that. Your passing at cruise which is 2400-2700rpm, But failing at 400-1000rpm idle test.
When they are testing it do you know if they are actually spinning the wheels on the dyno or just runing it in park?

 

[greenbeer]

It's on a dyno. They make you keep the wheels spinning at about 25mph at a certain rpm. There's a screen you watch that has a dial and a needle. You have to keep it in the green area until the test is complete.